 (at the network device).
 (at the network device).
 (at the transciever).
 (at the transciever).
40 PIN HI-DENSITY D-SUB FEMALE at the network device.
40 PIN HI-DENSITY D-SUB MALE at the transciever.
| Pin | Name | Dir | Description | 
|---|---|---|---|
| 1 | V |  | +5 Vdc/ 3.3 Vdc | 
| 2 | MDIO |  | MII Data Input/Output | 
| 3 | MDC |  | MII Data Clock | 
| 4 | RxD |  | Rx Data | 
| 5 | RxD |  | Rx Data | 
| 6 | RxD |  | Rx Data | 
| 7 | RxD |  | Rx Data | 
| 8 | Rx_DV |  | Rx Data Valid | 
| 9 | Rx_CLK |  | Rx Clock | 
| 10 | Rx_ER |  | Rx Error | 
| 11 | Tx_ER |  | Tx Error | 
| 12 | Tx_CLK |  | Tx Clock | 
| 13 | Tx_EN |  | Tx Enable | 
| 14 | TxD |  | Tx Data | 
| 15 | TxD |  | Tx Data | 
| 16 | TxD |  | Tx Data | 
| 17 | TxD |  | Tx Data | 
| 18 | COL |  | Collision | 
| 19 | CRS |  | Carrier Sense | 
| 20 | V |  | +5 Vdc/ +3.3 Vdc | 
| 21 | V |  | +5 Vdc/ +3.3 Vdc | 
| 22 | GND |  | Ground | 
| 23 | GND |  | Ground | 
| 24 | GND |  | Ground | 
| 25 | GND |  | Ground | 
| 26 | GND |  | Ground | 
| 27 | GND |  | Ground | 
| 28 | GND |  | Ground | 
| 29 | GND |  | Ground | 
| 30 | GND |  | Ground | 
| 31 | GND |  | Ground | 
| 32 | GND |  | Ground | 
| 33 | GND |  | Ground | 
| 34 | GND |  | Ground | 
| 35 | GND |  | Ground | 
| 36 | GND |  | Ground | 
| 37 | GND |  | Ground | 
| 38 | GND |  | Ground | 
| 39 | GND |  | Ground | 
| 40 | V |  | +5 Vdc/ +3.3 Vdc | 
Note: Direction is DTE (Network device) relative DCE (Transciever).
| Contributor: | Joakim Ögren, Mark S Stephenson | 
| Source: | Ethernet (IEEE802.3) page at Connectivity Knowledge Platform (Made IT) | 
| A Tech Doc at Cisco Systems | 
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  May be copied and redistributed, partially or in whole, as appropriate.
  Document last modified: 2002-01-10